Cause

Clue

Non-Anion-Gap Acidosis

Diarrhea

Hx; ↑ K⁺

• Enterostomy

Drainage

RF

Early chronic kidney disease

RTA

• Proximal

↓ K⁺_, presence of other proximal tubular defects (Fanconi Syndrome)

• Distal—hypokalemic

↓ K⁺; hypercalciuria; UpH >5.5

• Distal—hyperkalemic

↑ K⁺; nl PRA/aldo; UpH >5.5

• Distal—hyporeninemic hypoaldosteronism

↑ K⁺; ↓ PRA/aldo; UpH < 5.5

Dilutional

Massive volume expansion with saline

Ureterosigmoidostomy

Obstructed ileal loop

Hyperalimentation

Amino acid infusion

Acetazolamide, NH₄Cl, lysine HCl, arginine HCl, sevelamer-HCl

Hx of administration of these agents

Anion-Gap Acidosis

DKA

Hyperglycemia, ketones

RF

Late chronic kidney disease

Lactic acidosis (L-lactate)

Clinical setting + ↑ serum lactate

Alcoholic ketoacidosis

Hx; weak + ketones; + osm gap

Starvation

Hx; mild acidosis; + ketones

Salicylates

Hx; tinnitus; high serum level; + ketones; + lactate

Methanol

Large AG; concomitant respiratory alkalosis; retinitis; + toxic screen; + osm gap

Ethylene glycol

RF; CNS symptoms; + toxic screen; crystalluria; + osm gap

D-lactic acidosis

Small-bowel disease; prominent neuro symptoms

Propylene glycol

IV infusions, e.g., lorazepam; + osm gap; RF

Pyroglutamic aciduria, 5-oxoprolinuria

Large AG; chronic acetaminophen